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Old radiator Sizing

I am currently involved in another Historic Home. This one had 2 steam boilers. Currently, the home has only 1 steam boiler connected to the system. It is a gas, 400m and it has connected to it radiators with 881 sq ft of radiation, naturally all are painted and peeling. An older disconnected oil boiler has 3 pieces connected to it. The 1st one is a flat radiator like I have seen on ceiling except this one is hung vertically in an entrance hall. It has 12 sections and the size is in between the thin tubes and fat columns.Height is 26". All the sizing books and charts that I have acquired don't show this one. The other 2 units are fan coil units by Herman Nelson Co. , Mod # TSU 1011A & TSU 1211A. If you have any info on size, sq ft, etc. It would really help.
I am also considering adding these 3 units back into the gas boiler. I have about 70 ft of main to reach these, 4" to 2" and only the first half is insulated. PSI is set about 5#, boiler is equipped with feedwater tank, only vent in system that I found is within 5' of boiler on supply. This is a 2 pipe system.
Main part of job is relocate pipes for 2nd floor radiators[2] due to kitchen remodel. Customer did mention poor heating in farthest rooms and some close rooms.


  • When you say \"fan coil unit\"

    do you mean a unit heater that blows directly into the room, or is it connected to ductwork?

    Herman-Nelson was bought up by American Air Filter. You might try them to see if they have any old books around. Failing that, try to come up with something of similar physical size.

    For the wall rad, I usually use the column-type chart.

    Is this a Vapor system? If so, what type?

    We'd love to see pics!

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  • Randy_22
    Randy_22 Member Posts: 9
    radiator sizing

    This fan coil has a prop fan without duct. One unit is in the garage and the other is in a laundry room.
    This is on steam, 5#, standard setting whether needed or not as installed by someone who did not even write their name with marker on the unit, much less have a company service sticker on unit.
    I can send pictures the next time.
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